Underwater communicator



Feb. 15, 1966 3,235,835

HENRY-ANTHONY DEL GIUDICE ETAL UNDERWATER COMMUNICATOR Filed June 28,1963 INVENTORS. HENRY- ANTHONY de/ Gum/ca P5 T52 N. W000 BY THE/RATTORNEYS. Helm/s, KIECH, Russeu. & KERN United States Patent *93,235,835 UNDERWATER COMMUNICATQR Henry-Anthony del Giudice, Long Beach,and Peter N. Wood, Los Angeles, Calif., assignors to Celestronics Inc.,Long Beach, Calif., a corporation of California Filed June 28, 1963,Ser. No. 291,503 11 Claims. (Cl. 340-6) The present invention relates toa communication system for underwater and is particularly adapted foruse in connection with self-contained underwater breathing apparatus.

Prior underwater communication systems have utilized both an electricaltransmitting means carried by the speaker and an electrical receivingmeans carried by the listener. It is an object of this invention toprovide an underwater communicator which transmits sound waves directlythrough the ambient water medium and which may be heard without the aidof an articificial receiver.

It is another object of this invention to provide a small and lightunderwater communicator particularly suitable for use in connection withself-contained underwater breathing apparatus and one which is portableand carries its own self-contained power supply. Another object of thisinvention is to provide an underwater communicator having a heat sinktherein which is in contact with the ambient water medium fordissipating heat generated Within the communicator to the ambient watermedium.

It is a further object of this invention to provide an underwatercommunicator incorporating a dynamic transducer having a movablemembrane communicating directly with the ambient water medium solely onthe front side thereof and a voice coil having an electrical resistanceof approximately one-half ohm.

Still another important object of this invention is to provide such anunderwater communicator including a pressure regulating means forequalizing the pressures exerted on the front and rear sides of themovable membrane. A still further object of this invention is to providean underwater communicator with a pressure regulating means whichutilizes the compressed breathing air of the self-contained underwaterbreathing apapratus for equalizing the pressures exerted on the frontand rear sides of the movable membrane. It is an object of thisinvention to provide an underwater communicator, including thecombination of a housing, a transducer positioned within the housinghaving a movable membrane communicating with the ambient water mediumsolely on the front side thereof, a power supply positioned within thehousing for actuating the transducer, an amplifier unit within thehousing connected between the power supply and the transducer, means forcoupling an externally positioned microphone as an input to saidamplifier unit, and a pressure regulating means mounted within thehousing for controlling the difference in pressures exerted on the frontand rear sides of the movable membrane.

Still another important object of this invention is to provide anunderwater communicator, including the combination of a housing, atransducer positioned within the housing and having a movable membranecommunicating with the ambient water medium solely on the front sidethereof, a power supply positioned within the housing for actuating thetransducer, an amplifier unit within the housing connected between thepower supply and the transducer, means for coupling an externallypositioned microphone as an input to said amplifier unit, and a pressureregulating means including a pressure chamber with at least one aperturecommunicating with the ambient water medium, a flexible diaphragmmounted between "ice the aperture and the remaining interior of thehousing and movable between extended and compressed positions inresponse to the pressure differential between the interior of thehousing and the ambient water medium for controlling the ditference inpressures exerted on both the front and rear sides of the movablemembrane, first movable valve means positioned in the housing interiorof the flexible diaphragm, means for coupling a source of compressed airto the first valve means, with the valve means being movably actuable bythe diaphragm when in a compressed position for admitting compressed airinto the housing, and second movable valve means communicating with thehousing interior of the flexible diaphragm and movably actuable by thediaphragm when in an extended position for exhausting air from thehousing.

A further object of the invention is to provide a pressure regulatingmeans for an underwater device, including the combination of a housingfor the device, a pressure chamber located. within the housing with atleast one aperture communicating with the ambient water medium, aflexible diaphragm miunted between the aperture and the remaininginterior of the housing and movable between extended and compressedpositions in response to the pressure ditferential between the interiorof the housing and the ambient water medium for controlling the pressuredifferential therebetween, first movable valve means positioned withinthe housing interior of the diaphragm, means for coupling a source ofcompressed air to the first valve means, the first valve means beingmovably actuable by the flexible diaphragm when in a compressed positionfor admitting compressed air into the housing, and second movable valvemeans positioned within the housing communicating with the housinginterior of the diaphragm and movably actuable by the diaphragm when inan extended position for exhausting air from the housing.

The foregoing objects, advantages, features and results of the presentinvention, together with various other objects, advantages, features andresults thereof which will be evident to those skilled in the art towhich the invention pertains, may be achieved with the exemplaryembodiments described in detail hereinafter and illustrated in theaccompanying drawing, in which:

FIG. 1 is a longitudinal cross-sectional view of the present invention;

FIG. 2 is a vertical sectional view of the invention taken along theline 2-2 of FIG. 1;

FIG. 3 is a vertical sectional view of the invention taken along theline 3-3 of FIG. 1;

FIG. 4 is a vertical sectional view of the invention taken along theline 44 of FIG. 1; and

FIG. 5 is a partial longitudinal cross-sectional view of an alternativeembodiment of the present invention.

The underwater communicator of FIG. 1 includes a housing 12 comprising afirst section 14, a second section 16, and a third section 18.

The first section 14 is cylindrical and provides an axial opening 20 atthe forward end thereof defined by a radially inwardly directed flange22 and a radially outwardly directed flange 24 located at the rearwardend thereof. A perforated screen or grill 26 covers the axial opening 20and is mounted on the exterior face of the flange 22 by a mounting ring28 and screws 30.

A dynamic transducer 32 is mounted within the first section 14 on theinterior side of the flange 22. The transducer 32 includes an annularpermanent magnet 34 having an annular slot 36 located therein, anannular coil form 38 receivable within the slot 36 and longitudinallymovable therewithin, and a pair of lead-in contacts 40 having a slightlyaltered L-shape, the short leg of the L engaging the exterior surface ofthe coil form 38 and the longer leg of the L being secured between twoannular insulating rings 42, 44 and connected to a leadin wire 46. Thetransducer 32 also includes a coil 48 which is wound about the coil form38, thus securing the short leg of the L-shaped lead-in contacts 40between the coil 48 and the coil form 38, the coil having a resistanceof approximately one-half ohm allowing for maximum power output withinthe confined space provided the transducer 32. The use of the one-halfohm voice coil 48 is particularly desirable since it can be used in asmall space, is inexpensive, and does not require an output transformerin the amplifier unit 93. A movable membrane 50 comprised of a tough,flexible film such as Mylar or the like, is secured adjacent the pair oflead-in contacts 40 in fixed engagement with the forward edge of thecoil form 38. A central abutment pad 54 is disposed at the rear of themagnet 34. Apertures 56 in the magnet (FIG. 4) provide for air passagebetween the face and rear thereof. A seal ring 58 is mounted between thetransducer 32 and the interior of the flange 22. A pair of microphonewires 59 pass to the exterior of the housing 12 through a compressionseal 60 and may extend to a standard throat microphone 61 worn about theneck of the user.

The second section 16 of the housing 12 is mounted adjacent the firstsection 14 and is also cylindrical and provides a radially outwardlyextending flange 62 at the rearward end thereof and another radiallyoutwardly extending flange 64 at the forward end thereof. A transverseheat sink 66 spans the interior of the housing 12 and is mounted betweenthe first section 14 and the second section 16. More specifically, theradial flange 24 of the first section 14 and the radial flange 64 of thesecond section 16 are joined together by a plurality of bolt and nutcombinations 68. The transverse heat sink 66 is positioned between therespective radial flanges, 24 and 64, and a pair of annular ring seals70. A plurality of ports 72 is located in the heat sink 66 to permit thefree flow of air between the first section 14 and the second section 16.A threaded axial port 74 in the heat sink 66 has a threaded setscrew 76extending therethrough, which setscrew is longitudinally engageable withthe'abutment pad 54 at the rearward end of the transducer 32 for urgingthe transducer 32 forwardly into a seal fit against the radial flange 22of the first section 14. A transverse plate 78 spans the interior of thesecond section 16 and is spot welded at points 80 to the housing 12adjacent the rearward end of the second section 16. A plurality ofperipheral ports 82 is located in the transverse plate 78.

Located within the second section 16 is a power supply unit 84including'a twelve-volt direct current battery pack 86. A disposablebattery pack or a rechargeable battery pack may be used. If therechargeable battery pack is utilized, a recharging input jack 88 may bepositioned at the rear of the power supply unit 84. Three sockets 90, 91and 92 comprise the output connections for the battery pack 86.

An amplifier unit 93 is mounted on the rearward side of the heat sink66. The amplifier unit 93 is encased in a block of epoxy resin 94 andprovides three pins 95, 96 and 97 which extend outwardly from the epoxyresin block and mate with the sockets 90, 91 and 92 of the battery pack86. Transistors 98 used in connection with the amplifier unit 93 areshown as extending outwardly from the front side of the heat sink 66. Anamplifier on-off, rotary type, two-position switch 100 is mounted on theexterior of the first section 14 and is connected to the interior of thehousing 12 through a water-tight seal 102. The switch 100 is connectedto the amplifier 93 by wires 104.

An air space 107 located circumferentially of the power supply unit 84and within the second section 16 permits the free flow of air betweenthe ports 72 in the heat sink 66 and the ports 82 in the transverseplate 78.

The third section 18 of the housing 12, as shown in 4 FIG. 1 of thedrawing, includes an end plate 106 located at the rear thereof and aradially outwardly extending flange 108 at the forward end thereof. Thethird section 18 is secured to the second section 16 by securing theradial flange 108 thereof to the radial flange 62 of the second section16 by a plurality of bolt and nut combinations 110. Secured between therespective radial flanges 62 and 108 is an annular seal ring 112. Theend plate 106 is secured to the housing 12 by screws 114.

The third section 18 includes a pressure regulating unit including apressure chamber 116. Mounted between the end plate 106 of the thirdsection 18 and the housing 12 and spanning the pressure chamber 116 is aflexible diaphragm 118 comprised of rubber or the like. The flexiblediaphragm 118 has an annular groove 120 and a pair of axially locatedmetal engaging plates 122 on the interior and exterior sides thereof.

An inlet aperture 124 is located in the outer wall of the third section18 and a line 126 leading to a compressed air supply 127, such as thatof the divers selfcontained underwater breathing apparatus, is connectedthereto. Positioned within the inlet aperture 124 is a tilt valve 128including a valve seat 130, a valve member 132 movably engageable withthe valve seat 130, a spring 134 biasing the valve member intoengagement with the valve seat 130, and a tilt arm 136 extending fromthe valve member 132 and movably engageably with the flexible diaphragm118 when the diaphragm is in a compressed position for dislodging thevalve member 132 from the valve seat 130.

Located in the third section 18 of the housing 12 is an outlet aperture138 positioned exterior of the flexible diaphragm 118 but connected tothe housing space interior of the diaphragm 118 by an air conduit 140.Mounted within the outlet aperture 138 is a tilt valve 142 including avalve seat 144, a valve member 146 movably engageable with the valveseat 144, a biasing spring 148 engageable with the valve member 146 forurging it into engagement with the valve seat 144, and a tilt arm 150extending from the valve member 146 and movably engageable with theflexible diaphragm 118 when the diaphragm is in an extended position fordislodging the valve member 146 from engagement with the valve seat 144.

The end plate 106 of the third section 18 provides a plurality ofapertures 152 therein permitting the ambient water medium to flowtherethrough and exert a pressure on the flexible diaphragm 118.

An alternative embodiment of the pressure regulating unit 115 is shownin FIG. 5 of the drawing. Here the third section 18 is shown as havingan opening 154 spanned by a flexible diaphragm 156 having an annulargroove 158, a pair of axially located engaging plates 160, and aT-shaped engaging arm 167 extending forwardly from the inner sidethereof. The periphery of the diaphragm 156 is mounted on the thirdsection 18 between the housing 12 and a cap member 162, which is securedthereto by screws 164. The cap member 162 has apertures 163 therein topermit the passage of the ambient water medium therethrough in order tocommunicate with the diaphragm 156. In addition, a biasing spring 166 ispositioned within the cap 162 so as to exert an inward force on thediaphragm '156.

An inlet aperture 168 is located in the third section 18 and has a tiltvalve 170 positioned therewithin. A compressed air inlet line 172 isconnected between the tilt valve 170 and the compressed air supply. 'Thetilt valve 170 includes a valve seat 174, a valve member 176 movablyengageable with the valve seat, a spring 178 biasing the member 176 intoengagement with the seat 174, and a tilt arm 179 extending from thevalve member 176 and movably engageable with the T-shaped arm 167 of thediaphragm 156 when the diaphragm is in a compressed position fordislodging the valve member 176 from engagement with the valve seat 174.

An outlet aperture 180 is similarly located in the third section 18,interior of the diaphragm 156 and has a tilt valve 182 positionedtherewithin. The valve 182 includes a valve seat 184, a valve member 186movably enlgageable with the valve seat, a spring 188 biasing the member186 into engagement with the seat 184, and a tilt arm 190 extending fromthe valve member 186 and movably engageable with the T-shaped arm 167 ofthe diaphragm 156 when the diaphragm is in an extended position fordislodging the valve member 186 from engagement with the valve seat 184.

In actual operation, the underwater communicator may be mounted on theback of an underwater diver and will normally be positioned on top of oradjacent to the compressed air supply tanks used in connection withunderwater breathing apparatus. The user may at any time manuallyactuate the underwater communicator by turning on the switch 100 mountedon the exterior of the first section 14. Similarly the device may bemanually turned off at any time by the diver for the purpose ofconserving power when not in use.

A standard throat microphone may be secured to the users neck adjacentthe larynx or a microphone may be located in the users underwaterbreathing mask. In either situation, the signal generated by the userwhen speaking into the microphone will pass through the microphone lines59, through the amplifier 93, and into the transducer 32 through thelead-in wires 46. The change in current in the voice coil 48 caused bythe users voice will cause the coil form 38 to oscillate longitudinallywithin the annular slot 36 of the permanent magnet 34, thus causing themovable membrane 50 to vibrate and transmit direct audible impulses tothe ambient water medium. In this connection, it should be noted thatthe movable membrane 50 is firmly secured at its periphery within thefirst section 14 of the housing 12 and the rear- Ward side of themembrane 50 is completely sealed from exposure to the ambient watermedium. Thus, the housing 12 serves as a totally enclosed type ofloudspeaker enclosure preventing the impulses emanating from the rearside of the moving membrane from damping out those emanating from thefront side thereof.

While under water, a pressure differential will occur across the face ofthe movable membrane 50 of the transducer 32. Initially the interior ofthe housing 12, and correspondingly the rear side of the movablemembrane '50, will normally have the standard air pressure of theatmosphere just above the water surface. The exterior or front side ofthe movable membrane 50 will be subjected to an increased pressure dueto its exposure to the ambient water medium.

In order to provide maximum eificiency of the movable membrane 50 andprevent damage thereto, it is desirable to' control the difference inpressures on the front and rear sides thereof; the underwatercommunicator provides a pressure-regulating unit 115 which serves thispurpose. As illustrated in FIG. 1, for example, the ambient water mediumwill penetrate the pressure chamber 116 via the apertures 152 in the endplate 106 and the ambient water medium will come in contact with theflexible diaphragm 118 and exert an inward pressure thereon, causing theflexible diaphragm 118 to move toward a compressed position. As theflexible diaphragm 1 18 moves inwardly owing to the increased pressureof the ambient water medium as the diver descends, the interior engagingplate 122 will engage the tilt arm 136 of the tilt valve 128. The tiltarm 136 will pivot and dislodge the valve member 132 from engagementwith the valve seat 130. The opening of the tilt valve 128 admitscompressed air to the housing 12 through the compressed air supply line126 secured to the inlet aperture 124. The incoming compressed air willenter the housing interior of the flexible diaphragm 1 18 and flowequally throughout the interior of the housing 12 through the ports 82in the transverse plate 78, the ports 72 in the heat sink 66,

and the ports 56 in the transducer case 52. Therefore, the rear side ofthe movable membrane will be exposed to the increased air pressurewithin the housing 12, resulting in a pressure balance between the frontand rear sides on the movable membrane 50.

When a driver is ascending the adjusted increased pressure within thehousing 12 may be in excess of the pressure exerted on the front side ofthe movable membrane 50 by the ambient water medium. In this situation,the flexible diaphragm 118 will be urged rearwardly by the increasedinterior pressure. As the flexible diaphragm 118 moves'toward anextended position, the exterior engaging plate 122 will engage the tiltarm of the tilt valve 142. As the tilt arm 150 is moved by the extendingdiaphragm 118, the valve member 146 will be dislodged from engagementwith the valve seat 144 and the compressed air within the housing 12will pass through the air conduit 118 and out through the outletaperture 138. This exhaust operation will continue until the pressuredifferential between the interior of the housing 12 and the ambientwater medium is such that the diaphragm 118 relaxes toward a neutralposition thus seating the valve member 146 again in engagement with thevalve seat 144. It will be noted that the flexible diaphragm 118 mayrelax to a neutral position While the pressure within the housing isslightly higher than that exerted by the ambient water medium. Thisfeature will prevent water leakage around the valve seat 144.

In the alternative embodiment exhibited in FIG. 5 of the drawing, thepressure regulating procedure is the same although the structure isslightly modified. Herein, the T-shaped anm 167 extends from theinterior side of the flexible diaphragm 156 and during compression ofthe flexible diaphragm 156 engages the tilt arm; 179 of the tilt valveand during extension of the flexible diaphragm 156 engages the tilt armof the tilt valve 182. In addition, the third section 18 provides an endcap 162 mounted exterior of the flexible diaphragm 156 having apertures163 therein to provide communication between the ambient water mediumand the flexible diaphragm 156. Further, mounted within the end cap 162is a leaf spring 166 which is loaded between the end cap 162 and theflexible diaphragm 156. Thus, an inward biasing is provided by thespring 160 against the flexible diaphragm 156. This feature of theinvention is provided to assure the diver that during ascent, when theinterior pressure in the housing 12 is greater than the pressure exertedby ambient water medium, a slightly higher pressure will always remainwithin the housing 12. The sli htly higher pressure within the housing-12 which exists during the exhaust operation when compressed air ispassing out through the tilt valve 182 insures that no water will leakinto the housing around the valve seat 184.

Although exemplary embodiments of this invention have been disclosedherein for purposes of illustration, it will be understood that variouschanges, modifications, and substitutions may be incorporated in suchembodiments without departing from the spirit Olf the invention asdefined by the claims which follow.

We claim as our invention:

1. In an under-water communicator, the combination of:

a housing;

a transducer positioned within said housing and having a movablemembrane communicating with the ambient water medium solely on the frontside thereof;

a power supply positioned within said housing for actuating saidtransducer;

an amplifier unit within said housing connected between said powersupply and said transducer; an externally positioned microphone;

means connectable to said externally positioned microphone as an inputto said amplifier unit;

pressure regulating means mounted in said housing for controlling thedifference in pressures exerted on the front and rear sides of saidmovable membrane including a pressure chamber with at least one aperturecommunicating with the ambient water medium, a flexible diaphragmmounted between said aperture and the interior of said housing andmovable between extended and compressed positions in response to thepressure differential between the interior of said housing and theambient water medium for controlling the difference in pressures exertedon the front and rear sides of said movable. membrane, first movablevalve means positioned within said housing interior of said flexiblediaphragm, a source of compressed air, means coupling said source ofcompressed air to said first valve means, with said valve means movablyactuable by said diaphragm when in a compressed position for admittingcompressed air into said housing, and second movable valve meanscommunicating with the interior of said housing and movably actuable bysaid diaphragm when in an extended position for exhausting air from saidhousing.

2. An underwater communicator, as defined in claim 1,

in which said pressure regulating means includes:

an inlet aperture positioned in the wall of said housing interior ofsaid flexible diaphragm;

said coupling means connecting said compressed air source to said inletaperture;

said first valve means located in said inlet aperture comprising a tiltvalve movably actuable by said diaphragm when in a compressed positionfor admitting compressed air into said housing;

an outlet aperture located in the wall of said pressure chamber interiorof said flexible diaphragm; and

said second valve means positioned in said outlet aperture comprising atilt valve movably actuable by said flexible diaphragm when in anextended position for exhausting air from the interior of said housing.

3. An underwater communicator, as defined in claim 2, in which saidsecond valve means is positioned exterior of said flexible diaphragm,and in which a conduit means is provided between said outlet apertureand said second valve means.

4. In an underwater communicator, the combination of:

a housing;

a transducer positioned within said housing and having a movablemembrane communicating with the ambient water medium solely on the frontside thereof;

a power supply positioned within said housing for actuating saidtransducer;

an amplifier unit within said housing connected between said powersupply and said transducer; an externally positioned microphone;

means connectable to said externally positioned microphone as an inputto said amplifier unit; and

pressure regulating means mounted in said housing for controlling thedifference in pressures exerted on the front and rear sides of saidmovable membrane including a pressure chamber with at least one aperturecommunicating with the ambient water medium, a flexible diaphragmmounted between said aperture and the interior of said housing andmovable between extended and compressed positions in response to thepressure differential between the interior of said housing and theambient water medium for controlling the difference in pressures exertedon the front and rearward sides of said movable membrane, first movablevalve means positioned in said housing interior of said diaphagm, asource of compressed air, means coupling said source of compressed airto said first valve means, with said valve means movably actuable bysaid diaphragm when in a compressed position for admitting compressedair into said housing,

second movable valve means positioned in said housing interior of saiddiaphragm and movably actuable by said diaphragm when in an extendedposition for exhausting air from said housing, and actuating meansextending from said flexible diaphragm for movably engaging said firstand second valve means when said diaphragm is in said compressed andextended positions, respectively.

5. An underwater communicator, as defined in claim 4 having:

an inlet aperture located in the wall of said housing interior of saidflexible diaphragm;

said coupling means connecting said compressed air source to said inletaperture;

said first valve means positioned within said inlet aperture comprisinga tilt valve movably actuable by said diaphragm when in a compressedposition for admitting compressed air into said housing;

an outlet aperture located in the wall of said pressure chamber interiorof said flexible diaphragm;

said second valve means located within said outlet aperture comprising atilt valve movably actuable by said diaphragm when in an extendedposition for exhausting air from said housing; and

an actuating means extending from said flexible diaphragm movablyengaging the respective tilt valves of said first and second valve meanswhen said flexible diaphragm is in compressed and extended positions,respectively.

6. An underwater communicator, as defined in claim 5, in which aconstant biasing means is provided exterior of said flexible diaphragmfor exerting an inward pressure thereon.

7. In a pressure regulating means for an underwater device, thecombination of:

a housing for said device;

a pressure chamber located within said housing with at least oneaperture communicating with the ambient water medium;

a flexible diaphragm mounted between said pressure chamber and theinterior of said housing and movable between extended and compressedpositions in response to the pressure differential between the interiorof said housing and the ambient water medium for controlling thepressure differential;

first movable valve means positioned within said housing interior ofsaid diaphragm; a source of compressed air;

means coupling said source of compressed air to said said valve means,said first valve means being movably actuable by said diaphragm when ina compressed position for admitting compressed air into said housing;and

second movable valve means positioned within said housing communicatingwith the housing interior of said diaphragm and movably actuable by saiddiaphragm when in an extended position for exhausting air from saidhousing.

8. A pressure regulating means as defined in claim 7, in which saidsecond movable valve means is positioned exterior of said diaphragm, andin which a conduit means is provided between the housing interior ofsaid diaphragm and said second movable valve means.

9. A pressure regulating means as defined in claim 7, ing which saidsecond movable valve means is positioned within said housing interior ofsaid flexible diaphragm, and including actuating means extending fromsaid flexible diaphragm and movably cngageable with said first andsecond valve means when said flexible diaphragm is in compressed andextended positions, respectively, and biasing means exterior of saidflexible diaphragm for providing an inward pressure on said flexiblediaphragm.

10. In an underwater communicator, the combination:

a watertight housing having axially aligned first, second,

and third chambers therewithin;

a transducer mounted within said first chamber and having a movablemembrane communicating with the ambient water medium solely on the frontside thereof, and communicating with an air space within said 10 pressedposition for introducing compressed air from said source into saidhousing when the pressure within the housing is less than the ambientwater pressure, means responsive to the movement of said flexible firstchamber on the rearward side thereof; diaphragm toward an extendedposition for exhausta heat sink mounted between said first and seconding air from said housing into the ambient water chambers, said heatsink having a first portion extendmedium when the pressure within thehousing is greating to the exterior of said housing and communicating erthan the ambient water pressure, and an aperture with the ambient watermedium, and a second porin said third chamber communicating with the airtion extending transversely within said housing and space defined withinsaid second chamber to permit having a plurality of ports thereincommunicating with the air space within said first chamber;

free flow of the compressed air introduced by said pressure regulatingmeans throughout the interior of a power supply located within saidsecond chamber for actuating said transducer, said power supply beingspaced radially inwardly from the exterior wall of said housing anddefining an air space between the exterior of said power supply and saidhousing, which said housing and to the rearward side of the movablemembrane of said transducer.

11. An underwater communicator as defined in claim 10, in which saidpressure regulating means includes first movable valve means positionedwithin said housing inair space communicates with the ports located insaid terior of said flexible diaphragm, means coupling said heat sink;source of compressed air to said first valve means, said an amplifierunit mounted on said heat sink and confirst valve means being movablyactuable by said dianected between said power supply and said transducerphragm When in a position for admitting compressed air and spacedradially inwardly from the exterior wall into said housing, and secondmovable valve means posiof said housing to permit communication betweentioned within said housing communicating with the housthe air spacedefined between said power supply and ing interior of said flexiblediaphragm and movably acthe exterior wall of said housing and theplurality tuable by said diaphragm when in an extended position of portslocated in said heat sink; an externally posif r exhausting air fromsaid housing.

tioned microphone; means connectable to said externally positionedmicrophone as an input to said amplifier unit; and pressure regulatingmeans mounted within said third References Cited by the Examiner UNITEDSTATES PATENTS chamber for n rOlhng the difference in pressureslg/Ilunel exerted on the front and rear sides of said movable 5 10/1952V 9 179115.5 membrane including a pr s r chamber with at least 292317832/1960 W 1791 15.5 one aperture communicating with the ambient water2961639 11/1960 At 1 e ff 3% 1 4 medium, a fleXible phragm mountedbetween Said 2,978,672 4/1961 B anaso 340-14 aperture and the interiorof said housing and mov- 3079583 2/1963 i g "-"l 3 o 5 able betweenextended and compressed positions in 310O291 8/1963 i tt eta 34g 10response to the p s re differential between the in- 129 3/1965 L teriorof said housing and the ambient water medium aug et a1 340-5 forcontrolling the difference in pressures exerted on the front and rearsides of said movable membrane, a source of compressed air, meansresponsive to the movement of said flexible diaphragm toward a com-CHESTER L. JUSTUS, Primary Examiner.

R. A. FARLEY, Assistant Examiner.

1. IN AN UNDERWATER COMMUNICATOR, THE COMBINATION OF: A HOUSING; A TRANSDUCER POSITIONED WITHIN SAID HOUSING AND HAVING A MOVABLE MEMBRANE COMMUNICATING WITH THE AMBIENT WATER MEDIUM SOLELY ON THE FRONT SIDE THEREOF; A POWER SUPPLY POSITIONED WITHIN SAID HOUSING FOR ACTUATING SAID TRANSDUCER; AN AMPLIFIER UNIT WITHIN SAID HOUSING CONNECTED BETWEEN SAID POWER SUPPLY AND SAID TRANSDUCER; AN EXTERNALLY POSITIONED MICROPHONE; MEANS CONNECTABLE TO SAID EXTERNALLY POSITIONED MICROPHONE AS AN INPUT TO SAID AMPLIFIER UNIT; PRESSURE REGULATING MEANS MOUNTED IN SAID HOUSING FOR CONTROLLING THE DIFFERENCE IN PRESSURES EXERTED ON THE FRONT AND REAR SIDES OF SAID MOVABLE MEMBRANE INCLUDING A PRESSURE CHAMBER WITH AT LEAST ONE OPERTURE COMMUNICATING WITH THE AMBIENT WATER MEDIUM, A FLEXIBLE DIAPHRAGM MOUNTED BETWEEN SAID APERTURE AND THE INTERIOR OF SAID HOUSING AND MOVABLE BETWEEN EXTENDED AND COMPRESSED POSITIONS IN RESPONSE TO THE PRESSURE DIFFERENTIAL BETWEEN THE INTERIOR OF SAID HOUSING AND THE AMBIENT WATER MEDIUM FOR CONTROLLING THE DIFFERENCE IN PRESSURES EXERTED ON THE FRONT AND REAR SIDES OF SAID MOVABLE MEMBRANE, FIRST MOVABLE VALVE MEANS POSITIONED WITHIN SAID HOUSING INTERIOR OF SAID FLEXIBLE DIAPHRAGM, A SOURCE OF COMPRESSED AIR, MEANS COUPLING SAID SOURCE OF COMPRESSES AIR TO SAID FIRST VALVE MEANS, WITH SAID VALVE MEANS MOVABLY ACTUABLE BY SAID DIAPHRAGM WHEN IN A COMPRESSED POSITION FOR ADMITTING COMPRESSED AIR INTO SAID HOUSING, AND SECOND MOVABLE VALVE MEANS COMMUNICATING WITH THE INTERIOR OF SAID HOUSING AND MOVABLY ACTUABLE BY SAID DIAPHRAGM WHEN IN AN EXTENDED POSITION FOR EXHAUSTING AIR FROM SAID HOUSING.
 7. IN A PRESSURE REGULATING MEANS FOR AN UNDERWATER DEVICE, THE COMBINATION OF : A HOUSING FOR SAID DEVICE; A PRESSURE CHAMBER LOCATED WITHIN SAID HOUSING WITH AT LEAST ONE APERTURE COMMUNICATING THE AMBIENT WATER MEDIUM; A FLEXIBLE DIAPHRAGM MOUNTED BETWEEN SAID PRESSURE CHAMBER AND THE INTERIOR OF SAID HOUSING AND MOVABLE BETWEEN EXTENDED AND COMPRESSED POSITIONS IN RESPONSE TO THE PRESSURE DIFFERENTIAL BETWEEN THE INTERIOR OF SAID HOUSING AND THE AMBIENT WATER MEDIUM FOR CONTROLLING THE PRESSURE DIFFERENTIAL; FIRST MOVABLE VALVE MEANS POSITIONED WITHIN SAID HOUSING INTERIOR OF SAID DIAPHRAGM; A SOURCE OF COMPRESSED AIR; MEANS COUPLING SAID SOURCE OF COMPRESSED AIR TO SAID SAID VALVE MEANS, SAID FIRST VALVE MEANS BEING MOVABLY ACTUABLE BY SAID DIAPHRAGM WHEN IN A COMPRESSED POSITION FOR ADMITTING COMPRESSED AIR INTO SAID HOUSING; AND SECOND MOVABLE VALVE MEANS POSITIONED WITHIN SAID HOUSING COMMUNICATING WITH THE HOUSING INTERIOR OF SAID DIAPHRAGM AND MOVABLY ACTUATABLE BY SAID DIAPHRAGM WHEN IN AN EXTENDED POSITION FOR EXHAUSTING AIR FROM SAID HOUSING. 